WORK UNDERWAY ON CALATRAVA SPIRE IN CHICAGOAfter several redesigns, financing problems and months of speculation that Garrett Kelleher, executive chairman of Shelbourne Development Ltd., would not go ahead with Santiago Calatrava’s design for the 2,000-foot-tall "Chicago Spire," construction is now under way on the project, according to the Chicago Tribune. The design -- which required a change in city zoning for height and would make the building Chicago’s tallest, topping the Sears Tower -- takes advantage of "the new esthetic freedom made possible by the structural undergirding of the latest generation of supertall skyscrapers," according to the Tribune. Calatrava’s vision has the building appear to twist as it rises, with each floor shifted two degrees from the one below it -- a conceit which is practical as well as esthetic, according to the architect, serving to deflect the "Windy City"’s famous gusts.